1
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Phrase(s): stuff the ballot box
to fill a ballot box with illegal votes or with more votes than the number of actual voters. • The politician was charged with stuffing the ballot box. • The ballot box was stuffed with lots of votes for the crooked politician.
McGrawhill's American Idioms And Phrasal Verbs
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Put fraudulent votes in a ballot box, or otherwise cheat in an election. For example, The only way he'll win is if we stuff the ballot box. [Second half of 1800s]
American Heritage Idioms